Analytical approaches for the identification and quantitation of nitazenes: a review

Nitazenes, a class of high-potency novel synthetic opioids containing a benzimidazole moiety, are currently being reported across seized materials and drug-checking submissions, human biological matrices (postmortem and clinical/forensic), and community-level samples including wastewater. The analytical literature converges on a layered, matrix-oriented toolkit. Rapid presumptive strategies—vibrational fingerprints and ambient-ionization techniques—support triage in solids and field-adjacent contexts, while chromatographic separations coupled to mass spectrometry (LC-MS/MS/HR, and less frequently GC-MS) deliver selectivity and structure-aware confirmation for closely related analogues. In human biofluids, both targeted triple-quadrupole panels and HRMS suspect screening workflows are present for identification; validated quantitative methods consistently address calibration model and range, sensitivity (LOD/LLOQ), precision and accuracy, selectivity, carry-over, and matrix effects, often with explicit attention to isomer resolution. Cross-cutting issues recurring in the field include reference standard availability, isomeric/isobaric interferences, immunoassay cross-reactivity, and the promise of miniaturised sampling formats. Organised by matrix and analytical objective, this review provides enough information to enable efficient extraction of details at the method level, while ensuring a comprehensive coverage of the most important topics.